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Some time ago, perhaps several years, Maggy Murray, Bill’s wife, contacted me and volunteered some of Bill’s mementos for our website. Included were photographs of a number of launches of Hughes satellites. Unfortunately, these photos did not have a caption that identified the satellites being launched. I filed these away and forgot them until recently. Looking at the photos I realized that the launch vehicles were numbered and that would allow identification of the Hughes satellite being launched.

I found a website, KevinForsyth.net, that listed all the numbered Delta launches that allowed identification of the Hughes satellites. I also learned that the Delta is no longer in production and the last launch was on September 15, 2018 for a NASA mission, ICESAT-2. There were a total of 381 Delta launches with only 16 failures, a reliability of almost 96%.

The Pioneer Venus Orbiter incorporated a payload of 12 scientific instruments one of which was a fluxgate magnetometer provided by Chris Russell of UCLA, the principal investigator. Previous flybys of Venus had revealed that the magnetic field of Venus was much weaker than Earth’s. The resulting system requirements for the Orbiter magnetic fields are shown in Figure 4-2 in Reference 1. The most challenging requirement is that the remnant field at the magnetometer (after a 50-gauss demagnetization of the spacecraft) be 0.5 gamma or less. A Gauss is the usual measure used in magnetics—a gamma is 0.00001 Gauss. The earth’s surface magnetic field varies from 0.3 to 0.6 Gauss.

These requirements presented some issues that Hughes had not dealt with previously. At the beginning of the PV program no one at Hughes that I knew had experience in this area. Very fortuitously at this time we received an application from a TRW engineer, Chris Thorpe, who had performed these tasks for the TRW Pioneer spacecraft and had worked with Chris Russell previously. We hired him very quickly into the Perry Ackerman lab and assigned him to PV program. Chris was a delightful Englishman with a wry sense of humor and supported me in systems engineering and Tony Lauletta in science integration throughout the program.

Chris quickly demonstrated his knowledge of spacecraft magnetics and instituted a magnetic control program that included:

Formulating and maintaining a magnetic model of the Orbiter that predicted the magnetic field at the magnetometer

Limiting the type and amount of magnetic materials used in fabrication.

Using a nonmagnetic electroless nickel plate

Controlling the location and orientation of magnetically troublesome units on the equipment shelf.

Separating the magnetometer from the spacecraft by a deployable boom

Provide for magnetic compensation of units that utilize permanent magnets in their operation to reduce their field contribution at the magnetometer

Based on Chris’ calculations the boom length was set at 15 ft 6 in. (4.72 meters). As I recall Chris’s prediction was 14.5 feet and one foot was added to provide some margin. Chris maintained the magnetic model throughout the Orbiter development.

The boom, consisting of three hinged segments, is folded together and stowed on the orbiter shelf until deployed shortly after launch. The boom is secured by two redundant pyrotechnic pinpullers either of which when fired would release the boom for deployment. As the three segments extend, each hinged joint locks in the deployed position. A spin rate of 6.5 rpm provides the centrifugal force that ensures deployment and positive latching.

System level testing of the magnetometer boom proved to be problematic. The boom root hinge, when pyrotechnically released, was to deploy with the spacecraft spinning at 6.5 rpm. However, aerodynamic drag prevented the boom from fully extending in sea level density air. In order to validate the design it was necessary to encapsulate the spacecraft in a large plastic tent filled with 90% helium that provide a gas mixture with one fifth the density of air. The deployment test in this environment was successful.

Two system level magnetic tests are required—remanent and stray field determination. The remanent test is to determine the magnetic field of the quiescent spacecraft and requires a magnetic coil to cancel the earth’s magnetic field. The NASA Ames facility Magnetic Standards Laboratory and Test Facility in Mountain View, CA was used for this test and of course this required shipping the spacecraft to that facility. Tests were conducted with the spacecraft in a magnetized and demagnetized state. The stray field test to determine the magnetic field of the operating spacecraft was conducted in the Hughes high bay in the early morning to provide a magnetically quiet environment. The test results are presented in Figure 4.2 in from Reference 1. Chris Thorpe oversaw these tests.

According to Chris Russell: The most definitive measurements of the magnetic moment of Venus were obtained during the Pioneer Venus Orbiter mission in its first years of operation (1979-1981). Repeated low-altitude (~ 150 km) passes by that spacecraft over the antisolar region, coupled with dayside observations to the same altitude, proved the insignificance of a field of internal origin in near-Venus space. The observed fields for the most part could be explained as solar wind interaction-induced features. The new upper limit on the dipole moment obtained from the Pioneer Venus Orbiter wake measurements placed the Venus intrinsic magnetic field at ~ 10-5 times that of Earth.

At the conclusion of the Pioneer Venus program Chris and I were assigned to the newly started Galileo probe effort. After I left Galileo I lost track of Chris. Recently I learned that he passed away in 2000 at the age of 76. If someone can provide any biographical details for Chris I can add them to this post.

The two Pioneer Venus spacecraft were designed to be launched by the Atlas-Centaur for the 1978 Venus opportunity. Earlier studies had considered the Thor-Delta launch vehicle, but the Atlas-Centaur was judged by NASA to provide superior science performance and potential cost savings due to the greater payload capability. The starting point for spacecraft design is the allowable mass for the two spacecraft that is determined by the performance of the designated launch vehicle. Our customer, NASA’s Ames Research Center, adopted a specification weight for us to work to allowing for a cushion or contingency below the Atlas-Centaur launch capability. The ARC specification values, as a function of time, are shown in Figures 4-1 and 4-2 for the Orbiter and Multiprobe spacecrafts.

The 1978 Venus launch opportunity can be divided into two phases. The earlier launch opportunity, late May-early June, has a greater flight time to Venus and is a Type II interplanetary trajectory traversing an arc of more than 180O about the sun. However, this launch requires greater launch vehicle performance and provide less payload capability. The later launches in August, use a Type I interplanetary trajectory (less than 180O solar arc) and provide more than a 50% greater payload capability. As neither Hughes nor NASA Ames could support two simultaneous launch campaigns the Orbiter and Multiprobe require using both the early and late launch opportunities for the 1978 Venus opportunity. The Orbiter weight was significantly less than the Multiprobe and could launched during the earlier opportunity. An advantage is the 60% lower ∆V required for orbit insertion at Venus. The August launch opportunity is then available for the 60% heavier Multiprobe.

The final mass properties measurements for the two spacecraft are shown in Table 4-1 from the Reference 1. Note that the first row in the Table which is labeled “Spacecraft height” should read “Spacecraft weight.” Both spacecraft are stable spinners based upon the HS-333 design.

Joe Lotta was responsible for the Pioneer Venus mass properties analyses. This involved collecting inputs from each design area on a monthly basis and calculating the overall mass properties for each spacecraft. As shown in Figures 4-1 and 4-2 from Reference 1, over the course of the nearly four-year program weight growth was a constant concern. Considerable effort was devoted to trying to control weight growth and finding weight savings. At every opportunity trade-offs were considered and lists of weight savings with the cost detailed for each saving would be considered. Those weight savings characterized by lower dollars per pound would be implemented. Reference 1 documents 90 pounds of savings implemented for the Orbiter and 105 pounds for the Multiprobe. NASA ARC was able to provide increases in their specification weights to accommodate our weight growth. Some must have been due to Atlas Centaur performance improvements and the rest due to reduced contingencies and weight reserves. In retrospect it all came together and we witnessed two very successful missions.

The attached IDC, by Steve Dorfman, outlines for the Pioneer Venus team award fee based upon NASA’s evaluation of Hughes performance. Note that Tables 3 and 4 are missing and Table 7 is not mentioned in the text.

The attached letter, dated 27 August, 1979, from Dr. Wheelon to C. A. Syvertson, director of NASA’s Ames Research Center, analyzes the cost growth in Hughes’ Pioneer Venus program. The contract was cost plus award fee and what was at stake here was the determination by the Ames Performance Evaluation Board of Hughes’ award fee. This analysis was undertaken at the invitation of Ames to provide the causes for the program cost growth.

The following comments have been added by Steve Dorfman:

Of course I wrote the letter and NASA took mercy. They appointed Tom Young from NASA HQ to adjudicate and he came up with 2% fee in a Solomon-like decision which gave us a $2M profit instead of a significant loss due to our aggressive cost share proposal which, in hindsight, was way too risky. We had proposed this aggressive cost share, which had us going to negative fee (that is losing money) to be consistent with NASA HQ desire to have a management experiment in reducing the cost of planetary programs. However Charlie Hall ignored the “management experiment” and ran the program just as he had all Pioneer programs. In hindsight Charlie was right and NASA HQ was wrong and naive and so were we. Tom Young knew all this and that is why he gave us a modest fee.

In fact the program was an outstanding success in keeping costs low when compared with other NASA Planetary Programs. For $105M Hughes achieved a technically ambitious and difficult program. A bargain.

Jerry presented this paper presented at the 50th International Astronautical Congress, 4 – 8 October 1999, Amsterdam, Netherlands see www.iafastro.org. It details the recovery operations, led by Jerry, for the Hughes HGS-1 satellite that was launched for Asia Satellite Communications Ltd. Our search of the International Astronautical Foundation (IAF) online archives reveals that this paper or any reference to it is not available. The IAF indicates that no papers prior to 2004 are available. We feel that researchers should have online access to this paper as it is the definitive reference for this recovery mission.

Many wonderful and talented people at Hughes contributed to the success of this mission. A tribute to many of them as well as other contributors around the world is illustrated in the official mission poster which bears the signatures of all those folks.

Hughes Aircraft Company’s Space and Communications Group will have an additional $150 millions in business with the decision by the Federal Communications Commission to authorize five additional domestic satellite systems.

Hughes will build the satellites for the AMSAT, GTE/Hughes and ATT/Comsat systems. The company last week signed a $65.9 million contract with Comsat for four satellites to serve the continental United States, Alaska, Hawaii, and Puerto Rico.

(Previously, the FCC had approved an application by Western Union Telegraph Company, for which Hughes will build three satellites.)

Vice President Albert D. Wheelon, Group executive said the FCC decision was welcome for two reasons: “Approximately $200 million of private capital will be invested in the aerospace industry. Part of this investment will go to McDonnell-Douglas and General Dynamics companies for rocket boosters. The remainder is for the communications satellites to be built for the ATT/Comsat, GTE/Hughes, and ATT/Comsat systems.”

Dr. Wheelon added, “This is the largest single injection of private capital into the space industry and marks a turning point in that it represents the development of a substantial non-government market for spacecraft and booster manufacturers. This opportunity comes at a time when defense and NASA funding of satellite development is declining and is thus doubly welcome.”

“While communications satellites have been used to carry international traffic for 10 years, U. S. space technology will now be put to work for the 200 million people who supported the development of this technology. With the Western Union systems authorized early this year, the decision by the FCC guarantees that a breadth of innovative and improved domestic communications services will be available starting in 1974”

This year marks the 20th anniversary of the remarkable efforts that recovered the Hughes HGS-1 after a failed launch. This satellite launched as AsiaSat was placed in an unusable 51-degree inclined orbit after the fourth stage of the Proton launch vehicle failed. A recovery plan that involved two lunar flybys was developed and implemented. I documented this historic journey a year later and presented it at the 50th International Astronautical Congress in Amsterdam on October 4, 1999. This definitive paper describes the complex rescue limitations in detail, discusses the numerous mission considerations that had to be addressed, defines the nominal rescue maneuvers plan, and documents all (planned and ad hoc) maneuvers during the 68-day journey. This document will be posted on the Hughes heritage website for all to read the facts of the rescue.

May 13, 2018 marks 20 years since HGS-1 flew around the moon for the first time in a risky, epic rescue mission that attempted to transfer a Hughes HS601 HP spacecraft stranded in a highly inclined (51.6 degrees) geosynchronous transfer orbit (GTO, via a Proton upper stage failure ) into a useful geosynchronous orbit (GSO, similar to Syncom 2).

This mission was actually initiated on April 10, 1998, had an ad hoc second flyby of the moon on June 6, 1998 and achieved the best possible GSO orbit on June 16, 1998 with an inclination of about 7.5 degrees relative to the equator and a longitude south of Hawaii.

During this historic rescue, I wrote two US patents for Hughes that used single and multiple lunar flybys to assist transfer from any GTO to a GEO (geostationary orbit). Both patents were awarded in late 2000.

In the interim, a small company Innovative Orbital Design (IOD) filed suit against Hughes claiming we had infringed on their intellectual property. This is the same company that claimed to be responsible for giving Hughes the idea to use the moon for rescue with Belbruno’s “Fuzzy Boundary” theory. The court found that IOD’s claims were without merit and dismissed the suit by summary judgement. The court did not allow the case to proceed to trial and fined IOD for certain Hughes costs of defense. The initial legal and political attacks on this innovative Hughes accomplishment were successfully refuted.

Ironically, on the 10th anniversary (2008) of the HGS-1 flyby, a Lockheed Martin spacecraft, AMC-14, owned by SES, experienced a similar failure of the Proton upper stage resulting in a similar stranded orbit to HGS-1. I was employed by SES for one month to study a possible lunar flyby rescue. The lunar geometry in this case was near perfect and a double lunar flyby would restore roughly eight years of the nominal 15 – year GEO mission. The only requirement was for Boeing (who now owned my original patents) to allow the rescue to occur. Unfortunately, SES had a $50 million law suit against Boeing to replace a satellite, lost during a sea launch explosion, at the original cost. Boeing required dismissal of the law suit, SES refused and the rescue mission was aborted. Amen to any previous or future commentary of whether the patents were valid or unenforceable. In hindsight, though, I regret writing the patents that precluded a “near perfect” rescue of HGS-1’s stranded younger sister a decade later.

On the 15th anniversary (2013) a bombshell article, “Beyond GEO”, was published on the Space Review website (and republished on the Hughes heritage website). The story told by Rex Ridenoure reveals that an alternate rescue plan to the practical one that I devised was supported by Hughes personnel (Chris Cutroneo, Loren Slafer, and Cesar Ocampo). Rex acknowledges that Slafer told him on January 28 (a couple of weeks after his initial proposal) that the plan was impractical. I learned of this impossible plan from Ocampo a month later and instructed him not to reveal the official Hughes approach. Unfortunately, Rex reveals that Ocampo told Belbruno of the Hughes approach a month after he was instructed not to be a “leaker”. This occurred two weeks before our first maneuver Rex reveals there were subsequent leaks during the entire mission.

After several months in the blind with no contribution to this mission, Rex admits that he and Belbruno initiated their own PR campaign to sell their story about how the core enabling idea of using the Moon to salvage AsiaSat 3 entered into the option trade space at Hughes; and to insure this story was not buried by the personal or corporate motivations that apparently wanted to squelch the facts. Rex concluded in the article that “the story got out and stuck”. The rebuttal to “Beyond GEO” was published two months later on both the Space Review and Hughes heritage websites as 2 essays: “The Real Story”, part 1-Jerry Salvatore, mission director, and part 2-Mark Skidmore, project manager.

Remarkably after 20 years there still is controversy surrounding the facts of this recovery effort. On March 10, 2018, Chris Cutroneo wrote a blog for the Hughes heritage website entitled “HGS-1 Mission–Setting the Facts Straight.” This blog resurrects the Ridenoure and Belbruno PR campaign described above and purports to be factual. While Chris is entitled to his personal opinions, he is not allowed to distort the facts in his blog.

Chris Cutroneo, Loren Slafer and Cesar Ocampo worked with Ridenoure and Belbruno in January 1998 on an untenable rescue plan. Chris confirms that these Hughes personnel were told by the HGS project office in February to terminate all conversations with these outsiders. Subsequently, Cutroneo and Slafer voluntarily chose not to contribute or consult during any phase of the rescue mission. Chris’ statement “I relayed Cesar’s calculations and Rex’s information to Jerry via email, mentioning Rex’s company as well as the fuzzy boundary theory and that it was a novel theory but impractical” is absolutely “fake news”. As stated above I learned of this absurd plan from Ocampo in late February, well into the planning phase of the actual mission. This invented fact would apparently support his opinion in the blog, “But I believe we did have their idea in hand that helped us come up with the idea to do a lunar flyby and mimic the Apollo missions”.

Chris’ description of Cesar Ocampo’s position is correct. Cesar is a brilliant trajectory analyst who verified my original thesis and performed all trajectory studies during the entire mission. I named him a co-author on the definitive paper as well as the two patents issued because of his analytical contributions to the rescue mission. I was his principal sponsor when he was named “Hispanic Engineer of the Year” in 1998. However, I learned from Rex’s paper 15 years later that: He divulged our approach to Belbruno in late March; He continued his leaks to Belbruno during the mission; He refused to obey the HGS program office in April about public discussions of the mission; He wrote a paper seven years after the mission that lifted key paragraphs from the definitive paper (which has never been posted on the internet), embraced the Ridenoure PR propaganda and accused Hughes of unethical behavior.

Five years ago, Cesar shared a quote by me during the mission on the heritage website: “There are those who make things happen, others who watch it happen, and the rest who ask what happened. And Jerry falls in the first category.” In his response to my article on the HGS-1 mission Cesar adds, ‘I will be forever grateful to Hughes and individuals there, for having given me the opportunity to spend four wonderful years at Hughes, and the opportunity to work on HGS-1 and other missions. This has been a major highlight in my career.’

Chris further states in a final note, “HGS-1 achieved only a short period of time in GEO orbit post recovery. There was a more optimum time (better Earth, Moon, Sun geometry) to pull off the recovery plan, 6 months later than when we started it. It would have achieved a much longer life span (years), orbitally, for the satellite. It was unclear to me as to why this option was not selected.”

This is the second incorrect statement in his blog. I refer him to the trajectory design section of the definitive paper to help him understand the real options available. The fact is that given the lunar/spacecraft orbit geometry and spacecraft propulsion capability, no GEO orbit was achievable with the lunar flyby until 2029. Only GSO inclined orbits were achievable at about 2-year intervals. The first opportunity in April 1998 was selected. The resulting GSO orbit with an initial inclination of about 7.5 degrees was designed to become GEO (zero inclination) in 2007 using solar/lunar perturbations. The spacecraft was operated by Hughes Global Services for several years. The US Navy leased several transponders and it provided service to the Atlantic Fleet up to its deorbit. It was operational on 9/11 when an urgent call came for more capacity. Unfortunately, HGS-1 ran out of fuel and was placed in a multiyear pendulous GSO disposal orbit in late 2002 that positioned it over the dateline in 2007. This would minimize any possible collision hazard as the spacecraft traveled in the equator with no neighbors. It worked!

In the late 1960s the CIA was researching technology as part of the ZAMAN program to develop a satellite with the capability to directly image the ground below and send that imagery electronically to a ground station. One issue facing ZAMAN’s designers was how to store the imagery on the satellite and to then transmit it. If the satellite could only transmit the images while in view of a ground station this would dramatically limit how many images could be sent each day because the satellite would only be over a ground station for a limited amount of time. But there was a solution: instead of transmitting signals directly down to the ground, the imagery satellite could send them upward, to a communications relay satellite in a much higher orbit, and that satellite could relay the images to the ground. This approach added complexity, but provided numerous advantages, including increasing available transmission time.

This relay satellite, soon given the obscure name of Satellite Data System, could send the data down to a distant ground station, even one on the other side of the Earth from the reconnaissance satellite taking the pictures. The Satellite Data System, or SDS for short, was eventually developed under a unique management arrangement. Although it carried a highly classified mission payload—“black” in the jargon of the intelligence community, the satellite itself was developed and procured by the unclassified—“white”—Air Force Space and Missile Systems Office, thus straddling the edge of the shadowy world of satellite reconnaissance. A declassified history by Vance O. Mitchell, “The NRO, the Air Force, and the First Reconnaissance Relay Satellite System, 1969-1983,” describes how this unusual management relationship was developed—and almost fell apart—during its early years.

The CIA and NRO Approve Data Relay

In 1968, CIA official Leslie Dirks, who was then the program manager for ZAMAN, which had been underway for several years evaluating technology for a real-time imaging satellite, decided to rely on relay satellites rather than onboard data storage and transmission to a ground station for the ZAMAN satellite. By October 1969 Dirks named his assistant division chief as the manager for the relay satellites. The manager’s name is deleted in the declassified history, but he is described as conservative, detail oriented, and very methodical.

The National Reconnaissance Office (NRO) was the organization that was responsible for overseeing the development of intelligence satellites. The NRO included an Air Force component known as Program A and publicly acknowledged as the Secretary of the Air Force Office of Special Projects, or SAFSP. The NRO also included a CIA component housed in the CIA Deputy Directorate of Science and Technology’s Office of Development and Engineering and known as Program B, which was then leading the ZAMAN effort. Program A and Program B had often battled each other for primacy within the NRO. In 1969 NRO officials began planning for relay satellites, and by June they became a separate line item in the NRO’s budget. The relay satellite program formally began in spring 1970 when a preliminary evaluation selected a small number of civilian firms for a year-long system definition phase to begin in July of that year. The plan was to down-select to a single company in October 1971.

Using an additional satellite system in high orbit to relay images from ZAMAN satellites in low Earth orbit would be both expensive and complicated. But it also offered advantages over the direct transmission to ground approach, including longer transmission times. An added advantage of the relay system was that it enabled multiple satellite constellations, not just a single satellite at a time. Another advantage was that the imaging and relay satellites would be very far from each other and the ground station and it would be difficult for the Soviets to determine that the satellites were working together, thus increasing operational security.

Some of the details of both programs remain classified, but while these early decisions about the data relay satellite were being made, ZAMAN was still primarily a technology development program, not an approved satellite development program. Nevertheless, it was clear to those running the National Reconnaissance Program—the formal term for the collection of top secret intelligence satellites managed by the NRO along with their budgets—that these new systems were going to be very expensive. That created a dilemma for the National Reconnaissance Office leadership, who sought to be low-key even among those who had security clearance to know about the NRO.

Spreading the Responsibility and the Costs

On August 15, 1969, the NRO’s Executive Committee decided to give relay satellite development to the Space and Missile Systems Office (SAMSO). SAMSO was part of the Air Force Systems Command and not affiliated with the Secretary of the Air Force Special Projects office—the classified NRO Program A office—in Los Angeles. Unlike Program A, SAMSO was both overt and completely outside of the NRO, and giving a non-intelligence organization responsibility for a new satellite vital to national reconnaissance was extremely unusual. The NRO’s ExCom also gave the program an overt designation: the “Satellite Data System,” or SDS.

According to Vance Mitchell’s history of the relay satellite program, there were three reasons to give development responsibility for the Satellite Data System to SAMSO:

Funding it through Air Force channels would hold down the National Reconnaissance Program budget. The ExCom members were concerned about the NRO budget exceeding a billion dollars, believing that this was a threshold above which their program would receive added political scrutiny from the few elected officials who were cleared to know about the NRO. Other NRO programs had already shifted money into the Air Force side to keep the total NRO budget down. It was not until the early 1970s that the National Reconnaissance Program budget finally crossed the billion-dollar mark.

Having SDS as an Air Force program would imply to the Soviets that it was not connected to reconnaissance and therefore enhance mission security.

The Air Force Satellite Control Facility was responsible for communicating with satellites and had acquired considerable experience. In addition, the Aerospace Corporation had been evaluating data relay satellites in 1968 into 1969 and had become knowledgeable about the subject. Aerospace worked closely with the Space and Missile Systems Office.

SAMSO designated the SDS program as secret with a “special access required” annex. There were only two other SAR programs at the time. One was the Defense Support Program (DSP) missile warning satellite, and the other may have been what became the Global Positioning System. SAR allowed the release of selected information about the NRO’s communications relay payload without divulging critical items that might compromise its mission. The CIA’s connection to SDS and details of the NRO communications payload were confined to a special compartment within the NRO’s own BYEMAN security system. Anybody requiring access to this information had to be cleared by the NRO.

Once SAMSO was designated in charge of SDS, it immediately led to questions within SAMSO and the Air Force. Air Force personnel involved in SDS development believed that since the Air Force was providing the personnel, expertise and offices to run the SDS development, SAMSO was now more than a junior partner in somebody else’s program and should be treated as a full partner. Brigadier General Walter R. Hedrick Jr., Director of Space and Deputy Chief of Research and Development, wanted changes in SDS to make it more responsive to Air Force missions. Hedrick wanted the satellites to serve both Air Force and NRO requirements. He wanted to add secondary payloads to the spacecraft in addition to the communications relay payload.

CIA officials connected to the SDS development believed that the SDS satellites were supposed to have a single NRO communications relay payload and no other missions. They were concerned that the NRO might become a “customer” on its own relay satellite and have the satellite’s covert intelligence mission compromised in the process.

By November 1969 there was pressure to create a management agreement that both sides would accept. CIA officials agreed to allow Air Force secondary payloads on SDS, but demanded a guarantee that the intelligence relay mission still had priority. In March 1970, the NRO accepted the management changes demanded by the Air Force while the Air Force guaranteed the NRO communications mission top priority.

Selecting Satellites and Payloads for SDS

The contract definition phase for SDS began in August 1970, a few months later than planned. Two contractors were involved: Hughes, and one other aerospace firm whose identity was deleted from the official history but was either TRW or Ford Aerospace. Both companies, like Hughes, were involved in developing communications satellites.

One of the secondary missions initially proposed for SDS was relaying data collected by Air Force DSP missile warning satellites then in development. But in summer 1970 members of the DSP program office—then operating under the deliberately obscure designation of Project 647—began to have reservations about using SDS relays for DSP satellites. Later in the year the Project 647 office withdrew from participation in the SDS in favor of relaying DSP data directly to the ground. That decision required DSP to develop its own ground stations, including a politically sensitive ground station in Australia. It also meant that SDS again became a single payload satellite.

This change annoyed Grant Hansen, the Assistant Secretary of the Air Force for Research and Development. Hansen wanted dual or multiple users on SDS. In a January 1971 meeting with several reconnaissance officials he discussed the options. Hansen had justified SDS in front of Congress on the basis of it having more than one payload and did not want to go back to members of Congress and explain why that was no longer the case. In an effort to force both SAMSO and the NRO to develop other payloads for SDS, Hansen suspended funding to SDS and placed the program on temporary hold.

In August 1970 three orbital configurations for SDS were being evaluated. The favorite option for several intelligence officials involved putting the relay satellites in geosynchronous orbit. But this was soon rejected. Although it provided good global coverage, it had a high price tag and an unacceptable level of technical risk. The other two options offered less coverage. One of these involved placing satellites in highly-inclined, highly-elliptical orbits so that they would swing low and fast over the South Pole and then head high up over the northern hemisphere, putting them in line of sight with both a low-orbiting reconnaissance satellite over the Soviet Union and a ground station in the United States.

Hansen’s ploy to force SAMSO and NRO to develop other options for the SDS satellites finally started to bear fruit. By early March 1971 Air Force and intelligence officials had identified at least six possible secondary payloads and two were considered most feasible. One of these was relatively minor: a small S-band transponder on each satellite could relay communications between the headquarters of the Air Force Satellite Control and a remote tracking station at Thule, Greenland, ending reliance upon balky land lines.

Another communications payload would support the Single Integrated Operational Plan, the Air Force’s nuclear war-fighting strategy. SIOP required communications with Strategic Air Command B-52 Stratofortress bombers and KC-135 Stratotankers. The SIOP at the time depended on ground-based high frequency broadcasts, which were vulnerable to jamming and nuclear disruption. An SDS payload in Earth orbit would be less vulnerable and could provide coverage in northern regions that were hard to cover. But according to Mitchell’s SDS history, the SIOP payload was regarded as a “heavy mother” requiring a helix antenna, transmitters, receivers, additional solar cells and cabling and structures weighing over 136 kilograms (300 pounds). In late May 1971, the two contractor teams determined that the SIOP payload was not a good candidate and the Air Force ruled it out for SDS.

Grant Hansen was apparently displeased that once again SDS was being reduced to a satellite system with a very limited mission. A review board including representatives from Hansen’s office slashed SDS funding for Fiscal Year 1972 in an effort to force program managers to go back and find another payload for the satellites.

General Sam Phillips, who was then in charge of SAMSO but had previously played a major role in running NASA’s Apollo program, protested the funding cut. The relay program was reduced to minimum effort until they could reach an acceptable agreement, or the relay program was taken away from SAMSO and transferred back to the NRO.

Although the specific details are deleted from Mitchell’s history, Mitchell indicates that the SIOP communications payload was eventually incorporated into the SDS satellite design despite its substantial mass and power requirements.

Secrecy and its paperwork

According to Mitchell, by spring 1971 there was increasing USAF opposition to the special access requirements (SAR) in place for SDS and the two other space programs because of the difficulties they created for management and operations. Although at least one of the SARs was eliminated around this time, Deputy Director of the NRO Robert Naka wanted to keep the Satellite Data System’s SAR in place. Finally, in January 1972 Director of the NRO John McLucas removed the SAR from the SDS program and withdrew all relevant material into the NRO’s own BYEMAN security compartment.

General Phillips and one other officer did not think that an entirely covert SDS program was necessary, but they believed that SDS security should be tightened. They and NRO officials agreed that the NRO’s BYEMAN security compartment would be used to protect details on the satellite’s bandwidth, near-real-time operations, transmission, specific frequencies, and the NRO relationship. Documents about the program would be classified at the secret level and would only refer to the secondary payloads. They would also state that SDS satellites were deliberately “over-engineered” in case the Air Force wanted to add more payloads, thus explaining why such a large satellite had a relatively limited communications payload. Previously the NRO payload had been referred to as “User A” but documents would now indicate that User A had been deleted.

The birth of KENNEN

In September 1971 President Richard Nixon formally approved development of the ZAMAN electro-optical imaging system. By November its name was changed to KENNEN, although it would become better known to the public by the designation of its camera system, KH-11. With the imaging satellite development now underway, the Satellite Data System finally had a confirmed primary mission and a deadline requiring that it become operational before the first KENNEN satellite was launched. KENNEN was initially scheduled for an early 1976 launch, although this eventually slipped to late in the year.

The communications relay payload that was developed for the KENNEN used a 60 GHz frequency that did not penetrate the Earth’s atmosphere. This meant that if the Soviets listened in on the KENNEN they would detect no emissions coming from it, creating the impression that it was passive even while it was sending signals up to the SDS.

At an April 20, 1972, meeting of the NRO’s Executive Committee (ExCom), NRO Director John McLucas was satisfied with existing management arrangements for SDS. SAMSO would continue management, the NRO’s Program B—led by the CIA—would exercise technical oversight, and the Air Force would fund and publicly defend the program to Congress. The NRO officials also established a more streamlined chain of command from SAMSO to the Secretary of Defense level.

The NRO director also moved SDS’s BYEMAN security responsibilities from the CIA-led Program B to the Air Force-led Program A (SAFSP), which strengthened the appearance of a strictly Air Force project and enhanced Air Force authority over the program. He also ordered that there be no further mention at all of a third payload outside the classified BYEMAN security channel, which meant that only people with BYEMAN clearances could speak or know about SDS’s communications relay payload. Information prohibited from public release included the number of satellites, orbits, technical descriptions, launch dates, finances, and mention of ground facilities.

On June 5, 1972, SAMSO selected Hughes to build the satellites. According to a 2011 interview with former CIA and Hughes official Albert “Bud” Wheelon, the winning Hughes design was based upon the company’s proven Intelsat IV spin-stabilized satellite, which weighed over 700 kilograms. The first Intelsat IV had been successfully launched into geosynchronous orbit in January 1971. Although both Intelsat IV and SDS were spinning drums covered with solar cells, SDS had a different set of antennas mounted to a de-spun platform at its top.

Anthony Tortillo, a Hughes engineer, was assigned to the SDS program. Hughes had a problem getting sufficient numbers of its own personnel security clearances, so a number of Air Force officers at the captain and major level with the required security clearances were detailed to work at Hughes.

Changes in Payloads and Operations

The SDS’s primary payload was always the communications relay for the KENNEN reconnaissance satellites. The two secondary payloads were just that—secondary. In August 1974 the Secretary of the Air Force approved adding a third secondary payload to the satellites, the Atomic Energy Detection System. This was introduced starting with the third satellite. Similar nuclear detection payloads—also known as “bhangmeters”—were already carried on Defense Support Program satellites. They could detect nuclear detonations in the atmosphere and space.

According to declassified Air Force documents, the Air Force started procurement with a structural test model designated X-1, followed by a qualification model designated Y-1 and equipped with most of the electronic systems to demonstrate that the satellite could perform the functions it was designed for. The initial plan was to procure four flight spacecraft (designated F-1 to F-4) and refurbish Y-1 to be a flight spare.

By the first half of 1975, testing of X-1 was completed, assembly of Y-1 was completed and it was undergoing initial testing, and fabrication of F-1 was well underway. By November 1975, the Air Force approved procurement of two additional satellites, F-5 and F-6, which were supposed to be compatible with the space shuttle.

The first two SDS satellites were launched into orbit atop Titan III-34B rockets in June and August 1976. The first KENNEN was launched in December that same year. Although the satellites all worked, according to several sources there were early operational problems with getting them to smoothly work together.

In 1977, a CIA employee sold a copy of the KH-11 user’s manual to the Soviet Union, giving away many of the secrets of the KENNEN satellite. However, Mitchell’s history hints that the Soviet Union did not understand the connection between the KENNEN and SDS satellites until the summer of 1978, confirming a claim that program planners had made about SDS early on, that it would be difficult for the Soviets to figure out that the satellites in highly different orbits were part of the same mission, especially since the KENNEN did not appear to be transmitting while over Soviet territory.

The fourth and fifth SDS satellites were delivered in May and October 1980, and Y-1 was refurbished, redesignated F-5A, and delivered in May 1980. In 1981 the Air Force proposed purchasing satellite F-7. It is unclear how many of these satellites were eventually launched, and one or more may have been retired to a classified storage facility at the end of the program.

Eventually, the first series of satellites were replaced by an updated version designed to be compatible with the shuttle from the start and apparently based upon the large Hughes Intelsat VI communications satellite. The National Reconnaissance Office surprisingly released photos and video of these later block 2 satellites in the late 1990s. Equally surprisingly, in early 2017, NASA revealed that it had been offered a spare satellite from an unnamed government agency. That satellite was clearly one of these block 2 vehicles. (See “Spinning out of the shadows,” The Space Review, March 13, 2017.) At some point, possibly even early during the 1970s, the SDS program received the classified code name QUASAR. That name was reportedly still being used into the twenty-first century.

The More Things Change…

In October 1976, the Air Force announced long-range plans that did not include SIOP payloads on future SDS satellites. Instead, the SIOP payloads would be mounted on the planned Air Force Milstar communications satellites. Milstar was a highly ambitious and complex communications satellite system that would support multiple Air Force requirements. When first conceived, the Air Force planned to have Milstar satellites in geosynchronous orbit as well as a constellation of satellites in medium-altitude polar orbits. The satellites in their different orbits would be able to communicate with each other, creating a complex interlocking communications network around the Earth. They were also supposed to be protected against enemy jamming and hardened to survive the effects of nuclear weapons. If it worked as planned, Milstar would provide a tremendous leap in communications capability for multiple Air Force and other users.

The CIA’s Leslie Dirks asked members of his staff to evaluate including the SDS relay capability on the Air Force’s Milstar. The initial concept was for three Milstar satellites in polar orbits to perform the relay capability for future KENNEN satellites. But CIA officials quickly grew skeptical about this proposal. Milstar was going to be very complex and face technical risks and problems in development resulting in delays which could affect the KENNEN relay mission. In addition, the NRO’s communications relay payloads would then become secondary payloads for satellites that had many other Air Force missions. CIA officials questioned what would happen if one of the NRO’s payloads failed on a Milstar satellite—would the Air Force launch an expensive replacement satellite simply to fulfill the NRO’s requirement? Two of Dirks’ aides recommended against putting the KENNEN communications relay payload on Milstar and Dirks agreed.

Dirks’ decision proved to be a good one. The early Air Force plan was for Milstar to begin operations in 1982, but Milstar soon ran into major development problems. Ultimately, the first Milstar did not launch into space until 1994. The Air Force had to postpone plans to transfer the SIOP communications payload from SDS to Milstar, and SDS continued carrying SIOP payloads into the 1990s.

Shuffling Responsibilities

Dirks’ decision to not transfer the KENNEN communications relay payload to Milstar meant that the SDS program would have to continue, and since the Air Force no longer had a requirement for SDS, the program would have to be transferred to the National Reconnaissance Office, with NRO funding and BYEMAN security measures. In November 1981, NRO Director Pete Aldridge approved the transfer of responsibility for SDS.

Aldridge’s decision created controversy. Brigadier General Jack Kulpa, who headed SAFSP and was therefore the NRO’s Program A director, lobbied to transfer the SDS from SAMSO into Program A, arguing that this would provide continuity and Program A had sufficient experience to run the program, although KENNEN was run by the CIA’s Program B and there was still an ongoing rivalry between personnel in Programs A and B. Yet another suggestion was to create an NRO Program D office solely to manage the relay satellite program.

SDS Director Colonel Clyde McGill and his supervisor, SAMSO commander Lieutenant General Richard Henry, lobbied to leave SAMSO responsible for SDS. They argued that withdrawing SDS into the National Reconnaissance Program benefitted nobody. Both the NRO and the Air Force needed SDS to serve as a “bridge organization” that could work in both the white and black worlds and provide access to evolving technologies for both sides. Although Mitchell’s history of SDS is unclear on this point, apparently Henry and McGill were successful at convincing Aldridge to maintain SDS as a SAMSO-led program, at least for a few more years.

The NRO will apparently declassify information about the early years of the KENNEN program sometime in 2018. If it does, we may learn more about SDS and its mysterious dance between the black and the white space communities.

Dwayne Day is interested in hearing from anybody with stories about the SDS. He can be reached at zirconic1@cox.net.

In the early 1990’s, Hughes Space and Communications Group (HSCG) teamed with Hughes Network Systems (HNS) to develop a satellite based cellular communications system. This was to be a total end-to-end system. HSCG was responsible for the Space Segment (spacecraft, spacecraft on-orbit as well as launch operations, including the facilities, software for both spacecraft bus and payload, and launch vehicle procurement). HNS was responsible for the user and ground segments (ground hardware infrastructure, network management, gateway stations, as well as cell phones and the billing system). Project management, including overall “Big-S” Systems Engineering, was the responsibility of HSCG as the prime, requiring formation of a GeoMobile Business Unit within HSCG.

The spacecraft did not fit into either the existing HS601 product line nor the under development at the time HS701 product line, necessitating a unique spacecraft, labeled HSGEM. There were many new, unique requirements for HSGEM space segment, the following is a list of a few of the major challenges:

A single L-Band 12.25-meter aperture antenna to provide both transmit and receive communications. The Astromesh reflector is 18 ft in length by 44 inches in diameter stowed for launch and when fully deployed is a 52.5 ft by 40 ft ellipse with a 12 ft depth. A 128-element feed array provides in excess of 200 individually controllable spot beams.

Elimination of potential Passive Intermodulation Products (PIM) sources for the spacecraft bus and payload. The diplexer was a special challenge due to the single antenna and the significant difference between receive and transmit power at L-band.

Digital Signal Processor (DSP) to provide channelization, routing and beamforming; all functions previously performed by analog and passive hardware. The DSP included a mobile-to-mobile switch to allow for direct routing of mobile terminal to mobile terminal calls, thereby reducing round trip delay to a single hop. The DSP utilized state of the art at the time ASICs jointly designed and qualified by Hughes and IBM and manufactured by IBM. Flexible digital beamforming was a special challenge.

Common software for payload, spacecraft system test and launch plus on-orbit operations integrated from Commercial, off the shelf (COTS) products and HSCG developed DSP command and control.

Unique approach to North-South station keeping using the power of the payload to perform electronic beam steering vs chemical station keeping while operating in inclined orbit.

A development vehicle and the first two spacecraft were manufactured by HSCG, the Satellite Control Center by Raytheon and the Network Control Center and ground infrastructure by HNS. The first launch of a HSGEM spacecraft, however, occurred in the year 2000 after HSCG was bought by Boeing. Although Boeing activities are not discussed on this website, it is public information that the first HSGEM was successfully launched by Sea Launch and met or exceeded all requirements (space and ground), resulting in a very successful and happy customer. The satellite and ground systems are still operational today (2018) and revenue creating, exceeding the 12-year life requirement of the contract.

Key to the commercial success of this project was its efficient use of very valuable and much in-demand L-Band frequency spectrum. Ability to control more than 200 individual spot beams allowed for reuse of the same frequency spectrum more than 40 times and tailoring the coverage area to meet needs of specific customers. A comprehensive article, “The Hughes Geo-Mobile Satellite System”, was co-authored by HSCG (John Alexovich and Larry Watson) and HNS (Anthony Noerpel and Dave Roos) with major support from the rest of the “Big S” Systems Team and presented at the 1997 International Mobile Satellite Conference held in Pasadena California. The article is an excellent description of the end-to end system. Some of the key points are as follows (full article appears immediately following key points).:

HSGEM is sized to provide 16,000 voice circuits for 2 million subscribers, including presence of up to 10 dB of shadowing.

The maximum coverage area with over 200 beams, each approximately 0.7 degrees in diameter or 450 km across, is 12 degrees as viewed from geosynchronous altitude.

Dual mode terminals provide the ability to communicate with either the HSGEM or with local terrestrial cellular systems (GSM) for voice, data, facsimile, and supplementary services.

The HSGEM accommodates many features that support flexibility and reconfigurability as technology further advances, which has been demonstrated over 17 years (so far).